Highly Enantioselective Synthesis of α-Stereogenic Esters through Catalytic Asymmetric Michael Addition of 4-Oxo-4-arylbutenoates
作者:Zhen Wang、Donghui Chen、Zhigang Yang、Sha Bai、Xiaohua Liu、Lili Lin、Xiaoming Feng
DOI:10.1002/chem.201001129
日期:2010.9.3
Highly enantioselective Michael addition of 1,3‐dicarbonyl compounds and nitromethane to 4‐oxo‐4‐arylbutenoates catalyzed by N,N′‐dioxide–Sc(OTf)3 complexes has been developed. Using 0.5–2 mol % catalyst loading, various α‐stereogenic esters were obtained regioselectively with excellent yields (up to 97 %) and enantioselectivities (up to >99 % ee). Moreover, the reaction performed well under nearly
已开发出由N,N'-二氧化物-Sc (OTf)3络合物催化的1,3-二羰基化合物和硝基甲烷的高对映选择性Michael加成反应到4-氧代-4-芳基丁烯酸酯。使用0.5–2 mol%的催化剂负载量,可以选择性地获得各种α-立体异构酯,具有极佳的收率(高达97%)和对映选择性(高达> 99% ee)。此外,该反应在几乎无溶剂的条件下进行得很好。具有官能团的产物已准备好进一步转化,这表明了催化方法的潜在价值。根据实验结果和以前的报告,提出了一个可行的工作模型来解释激活和不对称诱导的起源。